Camera module

ABSTRACT

An embodiment of a camera module comprises: a lens portion; a front body on which the lens portion is mounted; a substrate portion arranged to be spaced from the lens portion in a first direction and coupled to the front body; an image sensor arranged on the substrate portion and provided to face the lens portion; a first fastener, one side of which is inserted into the front body such that at least a part of the substrate portion is coupled to the front body; and a first attachment portion arranged between the front body and the substrate portion, wherein the first attachment portion may comprise at least one through-hole formed between the front body and the substrate portion so as to couple the front body and the substrate portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of U.S. patentapplication Ser. No. 17/230,296 filed Apr. 14, 2021, which is acontinuation application of U.S. patent application Ser. No. 16/349,038,filed May 10, 2019 (now U.S. Pat. No. 11,009,778), which is a U.S.National Stage Application under 35 U.S.C. § 371 of PCT Application No.PCT/KR2017/013194, filed Nov. 20, 2017, which claims priority to KoreanPatent Application No. 10-2016-0154679, filed Nov. 21, 2016, whoseentire disclosures are hereby incorporated by reference.

TECHNICAL FIELD

Embodiments relate to a camera module for preventing a focal pointposition of a lens from deviating from a design range or preventing somecomponents from being deformed or damaged during an assembly procedure.

BACKGROUND ART

The content described in this part merely provides backgroundinformation related to embodiments and does not constitute the relatedart.

A camera module for various uses may be installed in a vehicle. Forexample, a camera module for ensuring rear vision during vehicle parkingmay be installed on a rear body of the vehicle.

In addition, a camera module may also be used in a vehicle black boxthat has been recently and very usefully used to track details ofaccident, cause of accident, and so on when a traffic accident occurs.In accordance with current trends, a camera module has been graduallyused as a recognition device for clearly and easily recognize asituation of a blind spot that is difficult to check with the unaidedeye by a driver or passenger of a vehicle.

In accordance with recent trends, so called smart cars, that is,vehicles including a collision warning system for pre-detecting andpreparing for front and rear collision possibility of a vehicle, acollision avoidance system for directly avoiding collision betweendriving vehicles by a control device installed in the vehicle instead ofby driving of a driver, or the like have been increasingly manufacturedand related technologies of the smart cars have been increasinglydeveloped.

Camera modules have been increasingly used as a recognition device of anexternal situation of such a smart car and, accordingly, in accordancewith current trends, vehicle camera modules have been increasinglyproduced and technologies thereof have also been increasingly developed.

A camera module may include an image sensor that is disposed at aposition to face a lens in an optical axis direction. During assembly ofthe camera module, a focal point of the lens is disposed at a positionwithin a design range on the image sensor.

However, there is the possibility that a position of a focal point of alens is outside a design range during an assembly procedure of thecamera module and, accordingly, there is a need to overcome this.

In addition, some components are deformed or damaged during the assemblyprocedure of the camera module and, accordingly, there is a need toovercome this.

Embodiments provide a camera module for preventing a focal point of alens from being outside a design range or some components from beingdeformed or damaged during an assembly procedure of the camera module.

The technical objects acquired by this disclosure are not limited to thetechnical objects mentioned above, and other unmentioned technicalobjects will be clearly understood by those skilled in the art, to whichthis disclosure belongs, from the following description.

In one embodiment, a camera module includes a lens unit, a front bodywith the lens unit installed thereon, a substrate unit spaced apart fromthe lens unit in a first direction and coupled to the front body, animage sensor disposed on the substrate unit and configured to face thelens unit, a first coupling element having one side inserted into thefront body and configured to couple at least a portion of the substrateunit to the front body, and a first adhesive unit disposed between thefront body and the substrate unit, wherein the first adhesive unitcouples the front body and the substrate unit and includes at least onethrough hole formed between the front body and the substrate unit.

In another embodiment, a camera module includes a lens unit, a frontbody with the lens unit installed thereon, a substrate unit spaced apartfrom the lens unit in a first direction and coupled to the front body,an image sensor disposed on the substrate unit and configured to facethe lens unit, a first coupling element having one side inserted intothe front body and configured to couple at least a portion of thesubstrate unit to the front body, a first adhesive unit disposed betweenthe front body and the substrate unit, configured to couple the frontbody and the substrate unit, and including at least one through holeformed between the front body and the substrate unit, and a rear bodycoupled to the front body and configured to accommodate the substrateunit and the image sensor, wherein the substrate unit includes a firstsubstrate having one surface on which the image sensor is installed andthat is disposed to face the lens unit, and at least one secondsubstrate disposed to be spaced apart from the first substrate in thefirst direction, and the front body includes a first protrusion thatprotrudes in a direction toward the substrate unit, includes a firstadhesive surface at an end of the first protrusion, and includes anoxide film that is formed on the first adhesive surface via corrosion.

According to embodiments, when air that is filled in a space formed bythe front body and the substrate unit expands while the first adhesiveunit is heated in order to be hardened, some of the filled air may bedischarged to the outside through the through hole and, accordingly,change in a focal distance of the camera module outside a design range,deformation and damage of the first adhesive unit or the substrate unitand the like due to expansion of air may be prevented.

According to embodiments, the front body and the substrate unit of thecamera module may be coupled through the active align procedure and,thus, a focal point of the lens unit coupled to the front body may bedisposed at an optimum position of the image sensor installed on thesubstrate unit, thereby enhancing the image quality of an image capturedby the camera module.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a camera module according to anembodiment.

FIG. 2 is an exploded perspective view of a camera module according toan embodiment.

FIG. 3 is a cross-sectional view of a camera module according to anembodiment.

FIG. 4 is a side view showing the case in which a rear body is removedfrom a camera module according to an embodiment.

FIG. 5 is an enlarged view of a portion A of FIG. 4 .

FIG. 6 is a diagram showing the substrate unit 300 and the firstadhesive unit 500 according to an embodiment.

FIG. 7 is a plan view showing the first substrate of FIG. 6 .

FIG. 8 is a diagram showing the lens unit and the front body accordingto an embodiment.

FIGS. 9 to 14 are flowcharts for explanation of a method of assembling acamera module.

DETAILED DESCRIPTION

Hereinafter, the embodiments will be described in detail with referenceto the accompanying drawings. The embodiments may be modified in variousways and may take various other forms, and specific embodiments will beillustrated in the drawings and described in detail herein. However,this has no intention to limit the embodiments to the specific formsdisclosed herein, and it should be understood that all modifications,equivalents, and substitutions may be devised within the spirit andscope of the embodiments.

Although terms such as, for example, “first” and “second” may be used todescribe various elements, the elements should not be limited by theterms. These terms are merely used to distinguish the same or similarelements from each other. In addition, the terms particularly definedtaking into consideration the configurations and functions of theembodiments are merely given to describe the embodiments and should notbe intended to limit the scope of the embodiments.

In the description of the embodiments, it will be understood that, whenan element is referred to as being formed “on” or “under” anotherelement, it can be directly “on” or “under” the other element or beindirectly formed with intervening elements therebetween. It will alsobe understood that “on” or “under” the element may be described relativeto the drawings.

In addition, relative terms such as, for example, “on/upper/above” and“beneath/lower/below”, used in the following description may be used todistinguish any one substance or element with another substance orelement without requiring or containing any physical or logicalrelationship or sequence between these substances or elements.

In addition, in the drawings, the orthogonal coordinate system (x, y, z)may be used. In the drawings, the x-axis and the y-axis define a planeorthogonal to the optical axis. For convenience, the optical-axisdirection (the z-axis direction) may be referred to as a “firstdirection”, the x-axis direction may be referred to as a “seconddirection”, and the y-axis direction may be referred to as a “thirddirection”.

FIG. 1 is a perspective view of a camera module according to anembodiment. FIG. 2 is an exploded perspective view of a camera moduleaccording to an embodiment. FIG. 3 is a cross-sectional view of a cameramodule according to an embodiment. For clear description, a firstadhesive unit 500 is omitted in FIG. 2 .

The camera module according to an embodiment may include a lens unit100, a front body 200, a substrate unit 300, an image sensor 400, thefirst adhesive unit 500, a rear body 600, and a first coupling element710.

The lens unit 100 may be disposed on a front side of the camera moduleand, light emitted from the outside of the camera module may betransmitted through the lens unit 100 and may be incident on the imagesensor 400 that is disposed to face the lens unit 100 in a firstdirection.

The lens unit 100 may include at least one lens or two or more lensesmay be aligned in an optical axis direction to form an optical system.The lens unit 100 may be installed on the front body 200.

As shown in FIG. 3 , a coupling method of the lens unit 100 and thefront body 200 may be, for example, a screw coupling method. That is, afemale screw thread may be formed on a hollow portion of the front body200 and a male screw thread may be formed on an outer circumferentialsurface of the lens unit 100 and, thus, the lens unit 100 and the frontbody 200 may be coupled to each other.

Water or other impurities may be introduced into the camera modulethrough a gap present at a coupling portion between the lens unit 100and the front body 200 and, thus, a sealing device such as an o-ring maybe installed in order to prevent this. For example, the sealing devicemay be installed in a space portion S formed between the hollow portionof the front body 200 and the outer circumferential surface of the lensunit 100, as shown in FIG. 3 .

The lens unit 100 may be installed on the front body 200 and may becoupled to the rear body 600 to form a space in which the substrate unit300 is accommodated. As shown in FIGS. 1 and 2 , a flange may be formedto protrude on a side surface of the front body 200 in order to becoupled with the rear body 600, as shown in FIGS. 1 and 2 .

The flange of the front body 200 may be coupled to an end of the rearbody 600, and the flange of the front body 200 and the end of the rearbody 600 may be coupled to each other by, for example, adhesives or thefront body 200 and the rear body 600 may be formed of a metallicmaterial and may be coupled to each other via fusion or the like.

In order to prevent impurities from penetrating the coupling portionbetween the front body 200 and the rear body 600, the coupling portionneeds to be sealed. Accordingly, when the front body 200 and the rearbody 600 are coupled to each other via adhesion, fusion, or the like,the coupling portion may be sealed.

According to another embodiment, the front body 200 and the rear body600 may also be coupled to each other using a coupling element such as abolt. In this case, a gasket or the like may be installed at thecoupling portion between the front body 200 and the rear body 600 toprevent impurities from penetrating the camera module.

The substrate unit 300 may be spaced apart from the lens unit 100 in afirst direction, may be coupled to the front body 200, and may include afirst substrate 310 and a second substrate 320.

The image sensor 400 may be installed on one surface of the firstsubstrate 310, and one surface on which the image sensor 400 isinstalled may be disposed to face the lens unit 100. The first substrate310 may be electrically connected to the second substrate 320, and mayinclude various devices and circuit wirings for transmitting andreceiving an electrical signal to and from the second substrate 320.

In particular, the second substrate 320 may include a power supplydevice for supplying power to the first substrate 310, and the powersupply device may be electrically connected to an external power source.Although FIGS. 2 and 3 illustrate the case in which one second substrate320 is configured, a plurality of second substrates that are spacedapart from each other in the first direction may be configured accordingto another embodiment.

The first substrate 310 may be coupled to the front body 200 by thefirst adhesive unit 500, and the second substrate 320 may be coupled tothe front body 200 by the first coupling element 710. A couplingstructure of the first adhesive unit 500, the first substrate 310, andthe front body 200 will be described below in detail.

As shown in FIGS. 2 and 3 , the first coupling element 710 may have oneside inserted into the front body 200 and may couple at least a portionof the substrate unit 300, i.e., the second substrate 320 to the frontbody 200. For example, the first coupling element 710 may include ascrew coupling bolt having one side on which a screw thread is formedand the other side on which a head is formed.

In order to insert the one side of the first coupling element 710 intothe front body 200, a second protrusion 220 may be formed on the frontbody 200.

That is, the front body 200 may include a first protrusion 210 thatprotrudes in a direction toward the substrate unit 300 and includes afirst adhesive surface 211 at an end of the first protrusion 210. Inthis case, the second protrusion 220 may protrude in a direction towardthe substrate unit 300 from the first protrusion 210 and may include afirst insertion groove 221 (refer to FIG. 8 ) into which one side of thefirst coupling element 710 is inserted.

As shown in FIG. 2 , a first through hole 322 that the first couplingelement 710 penetrates may be formed in the second substrate 320.

The second substrate 320 may be coupled to the second protrusion 220 bythe first coupling element 710. That is, the first coupling element 710may penetrate the first through hole 322 formed in the second substrate320 and may have one end that is inserted into the first insertiongroove 221 formed in the second protrusion 220 and, thus, the secondsubstrate 320 may be coupled to the second protrusion 220 in a state inwhich the second substrate 320 contacts an end of the second protrusion220.

As shown in FIG. 2 , a first escape groove 312 having a shapecorresponding to the second protrusion 220 may be formed in the firstsubstrate 310. Accordingly, the first escape groove 312 may be formed inthe first substrate 310 and, thus, the first substrate 310 may bedisposed adjacent to an end of the first protrusion 210 disposed belowthe first substrate 310 without being interrupted by the secondprotrusion 220.

The first substrate 310 and the second substrate 320 each includevarious devices and circuit wirings and, thus, may be spaced apart fromeach other in order to prevent the devices from being damaged or circuitwirings from being short-circuited if the devices or the circuit wiringscontact each other.

The second protrusion 220 may space the first substrate 310 and thesecond substrate 320 apart from each other in the first direction by apredetermined distance. That is, the second protrusion 220 may protrudefrom the first protrusion 210 in the first direction, and the firstsubstrate 310 may be disposed adjacent to an end of the first protrusion210. The second substrate 320 may be disposed at a position thatcontacts an end of the second protrusion 220.

Due to this structure, the first substrate 310 and the second substrate320 may be spaced apart from each other in the first direction by apredetermined distance by the second protrusion 220. The predetermineddistance in the first direction between the first substrate 310 and thesecond substrate 320 may be adjusted by appropriately adjusting thelength of the second protrusion 220 in the first direction.

The image sensor 400 may be disposed on the substrate unit 300 and maybe configured to face the lens unit 100. Light transmitted through thelens unit 100 may be incident on the image sensor 400 and the imagesensor 400 may capture an image of a subject.

The image captured by the image sensor 400 may be converted into anelectrical signal and may be transmitted to an external display device,a storage device, or the like.

The rear body 600 may be coupled to the front body 200 and mayaccommodate the substrate unit 300 and the image sensor 400 therein. Therear body 600 may be configured in the form of a box shape with an openone side and may be coupled to the flange included in the front body 200at an end of the open one side.

As described above, the rear body 600 may be coupled to the front body200 and may form a space for accommodating the substrate unit 300 andthe image sensor 400 therein.

FIG. 4 is a side view showing the case in which the rear body 600 isremoved from a camera module according to an embodiment. FIG. 5 is anenlarged view of a portion A of FIG. 4 .

The first adhesive unit 500 may be disposed between the front body 200and the substrate unit 300. The first adhesive unit 500 may couple thefront body 200 and the substrate unit 300, e.g., the first substrate 310to each other.

The front body 200 may include the first protrusion 210 that protrudesin a direction toward the substrate unit 300 and the first protrusion210 may include the first adhesive surface 211 disposed at an endthereof. In this case, the first adhesive surface 211 may refer to anend surface of the first protrusion 210.

The first substrate 310 may include a second adhesive surface 311 at aportion facing the first adhesive surface 211. In this case, the secondadhesive surface 311 may refer to a surface of the first substrate 310,on which the image sensor 400 is installed.

The first adhesive unit 500 may be formed by coating adhesives on thefirst adhesive surface 211 or the second adhesive surface 311. That is,the first adhesive unit 500 may be formed by coating adhesives on thefirst adhesive surface 211, coating adhesives on the second adhesivesurface 311, or coating adhesives on both the first adhesive surface 211and the second adhesive surface 311.

In this case, when the first adhesive unit 500 is formed by coatingadhesives only on the second adhesive surface 311, the adhesives may becoated on the second adhesive surface 311 in a shape corresponding to ashape of the first adhesive surface 211.

At least one through hole 510 may be formed between the front body 200and the substrate unit 300. As shown in FIGS. 4 and 5 , the through hole510 may be formed in one side of the first adhesive unit 500.

That is, the first adhesive unit 500 may be formed by coating adhesiveson portions of the first adhesive surface 211 and/or the second adhesivesurface 311 in such a way that a portion on which adhesives are notcoated is formed as the through hole 510 rather than coating adhesivesin the form of one complete closed curve on the first adhesive surface211 and/or the second adhesive surface 311. That is, the first adhesiveunit 500 may be formed like an open curve.

The through hole 510 is formed in the first adhesive unit 500 and, thus,when the first adhesive unit 500 is heated to harden the first adhesiveunit 500, the front body 200 and the substrate unit 300 are coupled and,then, the front body 200 and the rear body 600 are coupled and,accordingly, some of air that is filled in a space formed by the frontbody 200 and the substrate unit 300 and expands due to heating may bedischarged to the outside through the through hole 510.

That is, the through hole 510 may connect the space formed by the frontbody 200 and the substrate unit 300 to the outside and, thus, when airpresent in the space formed by the front body 200 and the substrate unit300 is heated, some of the air may be moved to the outside.

Due to this structure, when the first adhesive unit 500 is heated,deformation of the substrate unit 300, change in a focal distance of thecamera module, and the like, which are caused due to expansion of airpresent in the space formed by the front body 200 and the substrate unit300, may also be prevented.

According to an embodiment, when air that is filled in the space formedby the front body 200 and the substrate unit 300 expands while the firstadhesive unit 500 is heated in order to be hardened, some of the filledair may be discharged to the outside through the through hole 510 and,accordingly, change in a focal distance of the camera module outside adesign range, deformation and damage of the first adhesive unit 500 orthe substrate unit 300, and the like due to expansion of air may beprevented.

The front body 200 and the substrate unit 300 may be coupled by thefirst adhesive unit 500 using an active align procedure and, in thisregard, in order to easily perform the active align procedure, the firstadhesive unit 500 may include adhesives formed of thermosetting andultraviolet (UV) curable materials.

The active align procedure may be a procedure in which the substrateunit 300 is moved in the first direction to adjust a focal distancebetween the lens unit 100 and the image sensor 400 that face each otheror the substrate unit 300 is tilted, i.e., is rotated on the x-y planeperpendicular to the first direction to adjust the focal distancebetween the lens unit 100 and the image sensor 400, according to anembodiment.

In order to perform the active align procedure, the first adhesive unit500 may be pre-hardened while the active align procedure is performed,and a permanent hardening procedure may be performed on the firstadhesive unit 500 after the active align procedure is completelyperformed

Accordingly, adhesives for forming the first adhesive unit 500 may be,for example, hybrid adhesives that react with both UV and heat and ishardened.

During the active align procedure, UV may be irradiated to the firstadhesive unit 500 to pre-harden the first adhesive unit 500 in a statein which a focal distance between the lens unit 100 and the image sensor400 is adjusted.

After the active align procedure is completely performed, the firstadhesive unit 500 may be heated to permanently harden the first adhesiveunit 500. In this case, for example, the first adhesive unit 500 may beheated using an oven or the like.

According to an embodiment, the front body 200 and the substrate unit300 of the camera module may be coupled through the active alignprocedure and, thus, a focal point of the lens unit 100 coupled to thefront body 200 may be disposed at an optimum position of the imagesensor 400 installed on the substrate unit 300, thereby enhancing theimage quality of an image captured by the camera module.

FIG. 6 is a diagram showing the substrate unit 300 and the firstadhesive unit 500 according to an embodiment. FIG. 7 is a plan viewshowing the first substrate 310 of FIG. 6 . FIG. 8 is a diagram showingthe lens unit 100 and the front body 200 according to an embodiment.

As shown in FIGS. 6 and 7 , the first escape groove 312 may be formed inthe first substrate 310 in a shape corresponding to the secondprotrusion 220 and, accordingly, the first substrate 310 may be insertedbetween one pair of the second protrusions 220 via press fitting.

As shown in FIG. 8 , the first adhesive surface 211 may be configured inan octagonal shape including long and short sides, viewed in the firstdirection. As shown in FIGS. 6 and 7 , the first adhesive unit 500 maybe configured on the second adhesive surface 311 to surround the imagesensor 400, and the plurality of through holes 510 that are spaced apartfrom each other may be formed in the first adhesive unit 500.

However, although FIGS. 6 and 7 illustrate the case in which the firstadhesive unit 500 is formed by coating adhesives on the second adhesivesurface 311, the first adhesive unit 500 may be formed by coatingadhesives on the first adhesive surface 211 or coating adhesives on boththe first adhesive surface 211 and the second adhesive surface 311according to other embodiments.

The shape, position, number, and the like of the through hole 510 shownin FIGS. 6 and 7 are merely an embodiment and, the shape, position,number, and the like of the through hole 510 may be variously selectedand the through hole 510 may be disposed in the first adhesive unit 500.

In order to increase coupling strength between the first adhesivesurface 211 and the first adhesive unit 500, the first adhesive surface211 may be configured to increase surface roughness.

For example, the surface roughness of the first adhesive surface 211 maybe increased via machining. According to another embodiment, when thefirst protrusion 210 is formed of a metallic material, an oxide film maybe formed on the first adhesive surface 211.

In this case, the oxide film may be formed by corrosion of a surface ofthe first adhesive surface 211. The surface roughness of the firstadhesive surface 211 may be increased by the oxide film and, thus,coupling force between the first adhesive surface 211 and the firstadhesive unit 500 may be enhanced.

FIGS. 9 to 14 are flowcharts for explanation of a method of assembling acamera module. Hereinafter, the camera module assembly method accordingto an embodiment will be described in terms of a method of coupling thesubstrate unit 300 to the front body 200 using an active alignprocedure.

When the substrate unit 300 is coupled to the front body 200, a focalpoint of the lens unit 100 coupled to the front body 200 may be disposedat an optimum position of the image sensor 400 installed on thesubstrate unit 300. Accordingly, according to an embodiment, a pluralityof pieces of information on a focal point may be acquired to determinean optimum position while a position at which a focal point of the lensunit 100 is disposed is adjusted through the active align procedure and,the substrate unit 300 may be coupled to the front body 200 at thedetermined position.

In the camera module assembly method, the front body 200 to which thelens unit 100 is coupled may be fixed and, the substrate unit 300 may beconfigured to be moved with respect to the front body 200 during thecamera module assembly procedure. According to another embodiment, thesubstrate unit 300 may be fixed and, the front body 200 to which thelens unit 100 is coupled may be configured to be moved.

That is, the substrate unit 300 or the front body 200 may be configuredto be rotated around axes that are in parallel to first, second, andthird directions and to be moved in parallel to the first, second, andthird directions, during at least a portion of the camera moduleassembly procedure. This may be embodied through an assembly device forperforming the active align procedure.

The camera module assembly method may include preparation operationS100, adhesives coating operation S200, a focal point adjustingoperation, and adhesives hardening operation S500. In addition, themethod may include preparation operation S100, adhesives coatingoperation S200, the focal point adjusting operation, adhesives hardeningoperation S500, and adhesives coating and hardening operation S600 ofthe through hole 510.

After adhesives coating operation S200 is completed, an align operationmay be performed. In the align operation, the adhesives may bepositioned between a first surface of the front body 220 and a secondsurface of the substrate unit. In this case, the first and secondsurfaces may face each other and may be surfaces that are coupled toeach other via adhesives.

The focal point adjusting operation may be performed only once or may beperformed twice or more. According to an embodiment, the focal pointadjusting operation may include primary focal point adjusting operationS300 and secondary focal point adjusting operation S400. The focal pointadjusting operation may be performed only once and, but may be dividedinto primary and secondary operations and a plurality of focal pointadjusting operations may be performed in order to more precisely adjusta focal point.

As shown in FIG. 9 , the method may include preparation operation S100,adhesives coating operation S200, primary focal point adjustingoperation S300, secondary focal point adjusting operation S400, andadhesives hardening operation S500. In addition, the method may furtherinclude adhesives coating and hardening operation S600 of the throughhole 510.

Preparation operation S100 may include posture check operation S110 andposture correction operation S120.

In posture check operation S110, a posture of the front body 200 or thesubstrate unit 300 may be checked. In detail, whether the substrate unit300 or the front body 200 is disposed appropriately for a referencebased on a preset reference value.

According to an embodiment, the posture of the substrate unit 300 or thefront body 200 may be checked by measuring an angle at which thesubstrate unit 300 or the front body 200 is tilted based on the presetreference value with respect to axes parallel to at least one directionand/or a distance by which the substrate unit 300 or the front body 200is spaced apart from the preset reference value in at least onedirection.

In detail, the angle at which the substrate unit 300 or the front body200 is tilted around axes parallel to the first, second, and thirddirections and the distance by which the substrate unit 300 or the frontbody 200 is spaced apart from the preset reference value in the first,second, and third directions may be measured to check the posture of thesubstrate unit 300 or the front body 200. In posture check operationS110, the posture may be checked using a camera.

In posture correction operation S120, when there is a difference from apreset reference position, the substrate unit 300 or the front body 200may be moved to the preset reference position to correct the posturethereof in consideration of the tilt angle and/or the spaced distancethat are measured in posture check operation S110.

In this case, the substrate unit 300 or the front body 200 may berotated at a tilt angle around axes parallel to at least one directionor may be moved in parallel to at least one direction to correspond tothe preset reference value. According to an embodiment, the substrateunit 300 or the front body 200 may be rotated around axes parallel tothe first, second, and third directions and may be moved in parallel tothe first, second, and third directions.

In adhesives coating operation S200, adhesives may be coated on thefirst adhesive surface 211 formed on the front body 200 or the secondadhesive surface 311 formed on the substrate unit 300 and, as shown inFIG. 11 , adhesives coating operation S200 may include coating regiondetermination operation 5210, coating operation S220, and a defectexamination operation. The defect examination operation may includefirst defect examination operation S230 and second defect examinationoperation S240.

In coating region determination operation S210, a coating region ofadhesives may be determined. In detail, in a camera module according toan embodiment, the first adhesive surface 211 or the second adhesivesurface 311 may be the coating region of adhesives.

In coating region determination operation S210, a position at whichadhesives are actually coated may be determined among the first adhesivesurface 211 and/or the second adhesive surface 311. A camera may be usedto determine the coated position of adhesives.

When an adhesives coating device is used, information on the coatingregion may be preset in the adhesives coating device. Accordingly, thefirst adhesive surface 211 and/or the second adhesive surface 311 may becompletely disposed at the preset position in preparation operation S100and, the adhesives coating device may perform coating on the cotingregion that is present in the first adhesive surface 211 and/or thesecond adhesive surface 311.

In coating operation S220, the adhesives may be coated on the coatingregion. In the camera module according to an embodiment, the adhesivesmay be coated using the adhesives coating device in consideration of asmall coating area, a rapid process, and the like.

After coating operation S220, the defect examination operation may beperformed. In the defect examination operation, whether the coatedadhesives is coated on the preset coating region, whether the adhesivesare uniformly coated, whether a proper amount of adhesives are coated,whether a defect is present in the image sensor 400, or the like may beexamined.

Whether a defect is present in the image sensor 400 may be examined byexamining issues that may occur due to coating of adhesives. Forexample, whether a portion of the image sensor 400 is stained with epoxyor the like may be determined. The defect examination operation mayinclude a plurality of defect examination operations. According to anembodiment, the defect examination operation may be performed byperforming first defect examination operation S230 and second defectexamination operation S240.

In first defect examination operation S230, whether a defect is presentin the coated adhesives may be examined. In detail, in first defectexamination operation S230, whether the coated adhesives are coated onthe preset coating region, whether the adhesives are uniformly coated,whether a proper amount of adhesives are coated, or the like may beexamined. When a defect is discovered in the coated adhesives, thedefect may be removed by re-performing coating or additionallyperforming coating.

In second defect examination operation S240, whether a defect is presentin the image sensor 400 may be determined. During a coating procedure ofadhesives, the adhesives may be coated on the image sensor 400 and,thus, whether a defect occurs in the image sensor 400 due to coating ofadhesives on the image sensor 400 may be examined.

In detail, in second defect examination operation S240, whether a pixelincluded in the image sensor 400 is damaged, whether adhesives arecoated on a surface of the image sensor 400, whether the image sensor400 is normally operated, or the like may be examined. When a defect isdiscovered on the image sensor 400, the defect may be removed using anappropriate method. Second defect examination operation S240 may includecontents in first defect examination operation S230.

The focal point adjusting operation may be performed once but, may beperformed twice or more. According to an embodiment, the focal pointadjusting operation may include primary focal point adjusting operationS300 and secondary focal point adjusting operation S400.

In primary focal point adjusting operation S300, a position of thesubstrate unit 300 may be adjusted to acquire information on focalpoints at a plurality of positions, positions of the substrate unit 300and/or the front body 200 may be determined based on the acquiredinformation on the focal points, the positions of the substrate unit 300or the front body 200 may be adjusted according to the determinedpositions, and the substrate unit 300 or the front body 200 may bepositioned at the determined positions.

In primary focal point adjusting operation S300, a focal point of thelens unit 100 may be positioned in an enable region of the image sensor400 and, as shown in FIG. 12 , primary focal point adjusting operationS300 may include primary focusing operation S310, focusing accuracydetermination operation S320, and primary focal point position adjustingoperation S330.

In primary focusing operation S310, the camera module may be focused ata focal point. In detail, in primary focusing operation S310, thesubstrate unit 300 may be moved in at least one direction, for example,in the first direction to position the focal point of the lens unit 100in the enable region of the image sensor 400.

In focusing accuracy determination operation S320, primary focusingoperation S310 may be performed and, then, a focusing positiondetermined to be appropriate may be determined or identified base on theinformation acquired in primary focusing operation S310. Primaryfocusing operation S310 and focusing accuracy determination operationS320 may be performed simultaneously with primary focusing operationS310 or may be performed in the middle of primary focusing operationS310 or, after primary focusing operation S310 is completely performed,focusing accuracy determination operation S320 may be performed.

In focusing accuracy determination operation S320, whether a focal pointof the lens unit 100 is positioned in the enable region of the imagesensor 400 may be determined. In this case, whether the focal point ofthe lens unit 100 is positioned in the enable region of the image sensor400 may be determined by measuring a spatial frequency response (SFR)value of the camera module.

When the SFR value is outside a preset range, primary focusing operationS310 may be repeatedly performed again in such a way that the SFR valueis within the preset range.

In primary focal point position adjusting operation S330, the substrateunit 300 may be moved in parallel to at least one direction and/or maybe rotated around at least one axis to position the focal point of thelens unit 100 in the enable region of the image sensor 400.

In primary focusing operation S310, the focal point of the lens unit 100may be adjusted in at least one direction, that is, for example, in thefirst direction to position the focal point of the lens unit 100 in theenable region of the image sensor 400.

In primary focal point position adjusting operation S330, the focalpoint of the lens unit 100 may be adjusted in at least one direction toposition the focal point of the lens unit 100 in the enable region ofthe image sensor 400. According to an embodiment, the lens unit 100 maybe adjusted in the first, second, and third directions to position thefocal point of the lens unit 100 in the enable region of the imagesensor 400.

To this end, according to an embodiment, the substrate unit 300 may bemoved in parallel to the first, second, and third directions and may berotated around axes parallel to the first, second, and third directions.

After primary focal point position adjusting operation S330 isperformed, the SFR value may be re-measured. When the SFR value isoutside a preset range, primary focal point position adjusting operationS330 may be repeatedly performed again in such a way that the SFR valueis within the preset range.

When primary focusing operation S310 and primary focal point positionadjusting operation S330 are performed, the focal point of the lens unit100 may be positioned in the enable region of the image sensor 400 inthe first, second, and third directions.

In secondary focal point adjusting operation S400, the substrate unit300 or the front body 200 may be moved in parallel to at least onedirection or may be rotated around at least one axis to adjust aposition of the image sensor 400, at which the focal point of the lensunit 100 is disposed.

According to an embodiment, the substrate unit 300 may be moved inparallel and may be rotated to adjust the position of the image sensor400, at which the focal point of the lens unit 100 is disposed.

As shown in FIG. 13 , secondary focal point adjusting operation S400 mayinclude secondary focusing operation S420, difference value computingoperation S430, and secondary focal point position adjusting operationS440. In addition, secondary focal point adjusting operation S400 mayfurther include optimum focal point position computing operation S410.

In optimum focal point position computing operation S410, the SFR valueof the camera module may be measured to compute an optimum focal pointposition of the lens unit 100. That is, in a state in which primaryfocal point adjusting operation S300 is completely performed, the SFRvalue of the camera module may be measured and, an optimum focal pointposition of the lens unit 100 with respect to the image sensor 400 maybe computed based on the measurement value.

In this case, the measured SFR value may be measured with respect toportions of an image captured by the image sensor 400 and, thus, may bemeasured as a plurality of values. For example, a value corresponding tothe case in which the image quality of an image is highest may beselected among the plurality of measured SFR values and, the optimumfocal point position may be computed based on the selected value.

That is, the optimum focal point position may be computed assuming thatthe value corresponding to the case in which the image quality of animage is highest among the plurality of measured SFR values is indicatedover the entire image.

In secondary focusing operation S420, the camera module may be focusedat a focal point and the SFR value may be measured. In detail, insecondary focusing operation S420, the substrate unit 300 may be movedin at least one direction, for example, in the first direction to movethe focal point of the lens unit 100 from the enable region of the imagesensor 400.

In primary focusing operation S310, the focal point of the lens unit 100may be positioned in the enable region of the image sensor 400 but, insecondary focusing operation S420, the focal point of the lens unit 100may be moved not to deviate from the enable region of the image sensor400 and, thus, in secondary focusing operation S420, the substrate unit300 needs to be more precisely moved in the first direction by a smallerdistance than in primary focusing operation S310.

In difference value computing operation S430, a difference value betweenthe optimum focal point position of the lens unit 100, computed inoptimum focal point position computing operation S410, and the focalpoint position of the lens unit 100, measured in secondary focusingoperation S420, may be computed.

In secondary focal point position adjusting operation S440, thesubstrate unit 300 may be moved in parallel and/or may be rotated toremove the difference value of the focal point position of the lens unit100 and, thus, the focal point position of the lens unit 100 may bedisposed at the optimum focal point position.

That is, in secondary focal point position adjusting operation S440, thesubstrate unit 300 may be rotated around axes parallel to the first,second, and third directions and may be moved in parallel to the first,second, and third directions to dispose the focal point position of thelens unit 100 at the optimum focal point position or to dispose thefocal point position of the lens unit 100 at a position that is spacedapart from the optimum focal point position within a preset error range.

In adhesives hardening operation S500, the adhesives may be hardenedusing UV and heat and, adhesives hardening operation S500 may include atleast one SFR value measuring operation, at least one substrate unitmoving operation, and at least one hardening operation.

According to an embodiment, in adhesives hardening operation S500, theadhesives may be hardened using UV and heat and, as shown in FIG. 14 ,adhesives hardening operation S500 may include primary SFR valuemeasuring operation S510, moving operation S520 of the substrate unit300, secondary SFR value measuring operation S530, primary hardeningoperation S540, tertiary SFR value measuring operation S550, secondaryhardening operation S560, and quaternary SFR value measuring operationS570.

In primary SFR value measuring operation S510, the SFR value of thecamera module may be measured to check the first direction focal pointposition of the lens unit 100.

In moving operation S520 of the substrate unit 300, the substrate unit300 may be moved in at least one direction, for example, in the firstdirection to adjust a distance by which the lens unit 100 and thesubstrate unit 300 are spaced apart from each other in the firstdirection.

In secondary SFR value measuring operation S530, the SFR value of thecamera module may be measured to check whether the substrate unit 300 ismoved in the first direction by a preset distance.

When the substrate unit 300 is sufficiently moved or is not sufficientlymoved in the first direction, moving operation S520 of the substrateunit 300 and secondary SFR value measuring operation S530 may berepeatedly performed to move the substrate unit 300 in the firstdirection by a preset distance.

In primary hardening operation S540, UV may be irradiated to theadhesives to pre-harden the adhesives.

In tertiary SFR value measuring operation S550 that is a separate SFRvalue measuring operation different from primary SFR value measuringoperation S510, the SFR value of the camera module may be measured tocheck whether the first direction focal point position of the lens unit100 is the same as the measurement result in primary SFR value measuringoperation S510 or is within an error range.

When the first direction focal point position of the lens unit 100 iscompared with the measurement result in primary SFR value measuringoperation S510 and is outside the error range, the adhesives are in apre-hardened state still and, thus, moving operation S520 of thesubstrate unit 300, secondary SFR value measuring operation S530, andtertiary SFR value measuring operation S550 may be repeatedly performedin such a way that the first direction focal point position of the lensunit 100 is within the error range. As necessary, primary hardeningoperation S540 may be performed.

In secondary hardening operation S560, the adhesives may be heated topermanently harden the adhesives.

In quaternary SFR value measuring operation S570, after secondaryhardening operation S560 is performed, the SFR value of the cameramodule may be measured to lastly check whether the first direction focalpoint position of the lens unit 100 is the same as the measurementresult in primary SFR value measuring operation S510 or is within theerror range.

The method may include adhesives coating and hardening operation S600 ofthe through hole after adhesives hardening operation S500 is performed.

When gas in an internal space formed by the front body 200 and the firstsubstrate 310 is thermally hardened in adhesives hardening operationS500, various issues may occur while the internal gas expands.

To overcome this, the through hole 510 for connecting the space formedby the first substrate 310 and the front body 200 and the other spacemay be formed in the first substrate 310 and/or the front body 200, oradhesives may be coated in the form of an open curve and internal gasthat thermally expands may be discharged to the outside using a portionon which the adhesives are not coated, as the through hole 510.

However, after the thermal hardening operation is performed, impuritiesor the like may penetrate from the outside through the through hole 510and, thus, the through hole 510 needs to be blocked.

Accordingly, the method may further include adhesives coating andhardening operation S600 of the through hole of filling the through hole510 with adhesives, tape, or the like. The adhesives may be epoxy or thelike and may be epoxy to be hardened by irradiating UV.

Adhesives coating and hardening operation S600 of the through hole maybe performed to form a second adhesive unit filled in the through hole510.

According to an embodiment, the front body 200 and the substrate unit300 of the camera module may be coupled through the active alignprocedure and, thus, a focal point of the lens unit 100 coupled to thefront body 200 at an optimum position of the image sensor 400 installedon the substrate unit 300 and, thus, the image quality of an imagecaptured by the camera module may be enhanced.

Although only several embodiments have been described above, variousother embodiments are possible. The technical ideas of the embodimentsdescribed above may be combined into various forms unless they areincompatible techniques, and thereby new embodiments may be realized.

According to embodiments, when air that is filled in a space formed bythe front body and the substrate unit expands while the first adhesiveunit is heated in order to be hardened, some of the filled air may bedischarged to the outside through the through hole and, accordingly,change in a focal distance of the camera module outside a design range,deformation and damage of the first adhesive unit or the substrate unitand the like due to expansion of air may be prevented.

What is claimed is:
 1. A camera module comprising: a lens unit; a front body coupled to the lens unit and comprising a first protrusion protruding from one end thereof and a second protrusion protruding from the first protrusion; a first substrate disposed on the first protrusion of the front body; a second substrate disposed on the second protrusion of the front body and spaced apart from the first substrate; an image sensor disposed on the first substrate and configured to face the lens unit; a coupling element configured to couple the second substrate and the second protrusion of the front body; and a first adhesive unit disposed between the first protrusion of the front body and the first substrate, wherein the first adhesive unit is configured to couple the first protrusion of the front body and the first substrate and comprises at least one through hole formed between the first protrusion of the front body and the first substrate, wherein the second substrate comprises a first through hole that the coupling element penetrates, and wherein the first substrate comprises an escape groove having a shape corresponding to the second protrusion.
 2. The camera module of claim 1, wherein each of the first protrusion and the second protrusion protrudes toward the second substrate.
 3. The camera module of claim 1, wherein the first protrusion comprises a first adhesive surface at an end thereof, and the first substrate comprises a second adhesive surface at a portion facing the first adhesive surface, and wherein the first adhesive unit is disposed between the first adhesive surface and the second adhesive surface.
 4. The camera module of claim 3, wherein the second adhesive surface have a shape corresponding to a shape of the first adhesive surface.
 5. The camera module of claim 3, comprising an oxide film formed on the first adhesive surface.
 6. The camera module of claim 1, wherein the second protrusion comprises an insertion groove into which at least one portion of the coupling element is inserted.
 7. The camera module of claim 1, wherein the first adhesive unit is configured to surround the image sensor.
 8. The camera module of claim 7, wherein the at least one through hole comprises a plurality of through holes spaced apart from each other.
 9. The camera module of claim 1, wherein the first adhesive unit is formed of thermosetting and ultraviolet curable material.
 10. The camera module of claim 1, comprising a rear body coupled to the front body and configured to accommodate the first substrate, the second substrate, and the image sensor.
 11. The camera module of claim 10, wherein the front body comprises a flange formed to protrude on a side surface thereof and one end of the rear body is coupled to the flange of the front body.
 12. The camera module of claim 1, wherein the front body comprising a first surface facing the lens unit and a second surface opposite to the first surface, and wherein the first protrusion is configured protrude from the second surface of the front body toward the second substrate.
 13. The camera module of claim 1, wherein the second protrusion comprises two protrusions spaced apart from each other, and wherein the escape groove comprises two grooves corresponding to the two protrusions, and wherein the coupling element comprises two coupling elements corresponding to the two protrusions, and wherein the first through hole of the second substrate comprises two through holes corresponding to the two coupling elements.
 14. The camera module of claim 1, comprising a second adhesive unit filled in the at least one through hole.
 15. The camera module of claim 1, comprising a power supply device disposed on the second substrate and configured to supply power to the first substrate.
 16. A camera module comprising: a lens unit; a front body coupled to the lens unit and comprising a first surface facing the lens unit, a second surface opposite to the first surface, a first protrusion protruding from the second surface, and a second protrusion protruding from the first protrusion; a first substrate disposed on the first protrusion of the front body; a second substrate disposed on the second protrusion of the front body and spaced apart from the first substrate; an image sensor disposed on the first substrate and configured to face the lens unit; a coupling element configured to couple the second substrate and the second protrusion of the front body; and a first adhesive unit disposed between the first protrusion of the front body and the first substrate, wherein the first protrusion comprises a first adhesive surface at an end thereof, and the first substrate comprises a second adhesive surface at a portion facing the first adhesive surface, and the first adhesive unit is configured to couple the first adhesive surface and the second adhesive surface, wherein the first adhesive unit comprises at least one through hole formed between the first protrusion of the front body and the first substrate, wherein the second substrate comprises a first through hole that the coupling element penetrates, wherein the first substrate comprises an escape groove having a shape corresponding to the second protrusion.
 17. A camera module comprising: a lens unit; a front body coupled to the lens unit and comprising a first surface facing the lens unit and a second surface opposite to the first surface; a first substrate disposed on the second surface of the front body; a second substrate disposed on first substrate and spaced apart from the first substrate; an image sensor disposed on the first substrate and configured to face the lens unit; a first adhesive unit configured to couple the front body and the first substrate, wherein the front body comprises: a first protrusion disposed between the second surface and the first substrate, a second protrusion disposed between the first protrusion and the second substrate, wherein the first adhesive unit is disposed between the first protrusion of the front body and the first substrate and comprises at least one through hole formed between the first protrusion of the front body and the first substrate, the camera module comprising a coupling element configured to couple the second substrate and the second protrusion of the front body, wherein the second substrate comprises a first through hole that the coupling element penetrates, wherein the first substrate comprises an escape groove having a shape corresponding to the second protrusion. 